Earth changes?

The phrase "earth changes" is often used to refer to some kind of disastrous event that will adversely affect much if not most life on Earth, including human life. There is thought about preparing ourselves for it, but the phrase is vague about what it could be.

CMEs, SPEs

Among the kinds of CMEs that can severely threaten much of the life on Earth are the coronal proton ejections (CPE) or Solar Proton Events (SPEs)  that have occurred several times in geologic history. One such event today could wipe out much of humanity and leave the Earth devastated. It could bring radiation, massive wildfires, and other destructive events.

It differs in severity from coronal mass ejections like the Carrington event of 1859, Those are CMEs, but do not in general threaten life rather than power grids, which could be devastating enough in this modern age of dependence on electronic devices of all kinds. There are calls such as the Shield Act to harden electric grids against them.

The main suspected SPE impacted the earth about 12,900 years ago. There may have two such events, 12,837 years BP and 12,639 years BP. They could have been a principal cause of the final termination of the Pleistocene megafauna and even of several genera of smaller mammals and birds. There is also evidence of one such event in 2012 that missed the Earth by only two weeks. One of the things that it does that could cause mass extinctions is to raise the level of proton (cosmic ray) bombardment to fatal levels. They are also suspected of causing massive, planet spanning wildfires.

Grazing rogue planets

There are interstellar objects that might make a grazing contact with the sun, We recently had one such object, Oumuamua, an odd-shaped body about ten times longer than it was wide, with other strange attributes. The general name for interstellar planets, not bound to a particular star, is rogue planet.. Most of them are expected to be round. They could be as large as other planets. The term generally applies to a rocky object, likely with a hot core, that could wander among the stars, and could provide a site for an outpost for star travelers, if the core is hot enough to geothermally support such an outpost.

Notes:

1. Did A Massive Solar Proton Event Fry The Earth?
2. Solar flare nearly destroyed Earth 2 years ago: NASA
3. Sun Could Unleash a 'Superflare' Hundreds of Thousands of Times More Powerful Than Any Known Flare
4. Ice Samples Reveal a Massive Sun Storm Hit Earth in Ancient Times...And It Could Happen Again
5. Coronal mass ejection — An event like the 1859 Carrington event could disrupt power grids.
6. Shield Act — Would protect power grids from coronal mass ejections, and from EMP attacks, but not the rest of the electronic infrastructure on which our economy depends.
   
7. Rogue planet — Planetary body not gravitationally bound to a star.
   
8. Oumuamua — Odd-shaped interstellar object flys through solar system.
   
9. Fastest Star in the Galaxy Has a Strange Origin — Moves about 26 million miles an hour. 
10. Solar Storm Threat Analysis, James A. Marusek, Impact, Bloomfield, Indiana 4742. also Solar Storm Disaster Preparedness Plan
11. Nearby Earth-like exoplanet Proxima b slammed by super flare that may have wiped out any possibility of alien life.
    
12. Solar Flare Survival, Marc Remillard
13. What Would Happen if a Massive Solar Storm Hit the Earth?
14. Getting Ready for the Next Big Solar Storm, NASA
15. Mars Colonists Could Live in Lava Tubes Beneath the Surface  — Could fit entire cities into such tubes.
16. Living Underground on Other Worlds  — We can see skylights of partially collapsed tubes.